Engine drifting-valve.



V. P. McVOY.

ENGINE DRlFTiNG VALVE.

APPLICATION men FEB. a. ma.

1 fi fiu Patented June 12, 1917.

gwwntoz tinrrnn s'rarns r a rnn'r oration.

VINCEN P. MGVOY, OF MOBILE, ALABAMA, ASSIGNOE OF ONE-HALF TO JOSEPH 1V1. WALSH, OF MOBILE, ALABAMA.

ENGINE DRIFTING-VALVE.

Specification of Letters Patent. -g ma June 12, 1917,

Application filed February 3, 1916. Serial No. 75,962.

Y '0 all whom it may concern:

Be it known that I, VINonN P. MoVoY, a citizen of the United States, residingat Mobile, in the county of Mobile and State of Alabama, have invented certain new and useful Improvements in Engine Drifting- Valves, OfWlllCll the following is a specification.

This lnvention relates to certain new and useful improvements in whatare known as f drifting valves for locomotives and it has for its objects among others to provide an" improved valve of this character wherein I guard against hammering of the valve upon its seat, thereby adding greatly to the life of the device and consequent wear, as well as reducing the necessity for overhauling and repairs.

I provide a novel form of valve, employing a double piston, with provision for seepage of the steam from one side of the piston to the other, thereby preventing too rapid movement and the consequent hammering of the valve agamst its seat.

The piston is provided with a dependingportion having ports cooperating with aported member in such a manner as to cause the valve when raised to balance itself by reason of the impact of the steam against the bottom of such extension.

Within the head of the differential piston I dispose a spring normally acting upon the valve carried by the piston to force the same to its seat. Nhen the piston is moved outward, the tension of the spring on said valve is reduced, so that the valve is returned'to its seat under minimum tension and all liability of breakage of the stem which often happens when the valve is returned to its seat under great pressure or tension, is prevented.

Other objects and advantages of the 1nvention will hereinafter appear and the novel features thereof will be particularly IFi'gl 2 is an elevation of the depending portion of the double piston.

Fig. 3 is a cross section on the line 3-3 of 2, looking in the direction of the arrows.

Fig. 1 is a cross section on the line 4l1 of Fig. 2, looking in the direction of the arrows.

Like numerals of reference indicate like parts throughout the different views.

Referring to the drawings,

1 designates the body portion of the valve having at one side an extension or inlet 2 for a union coupling 3 for the sleeve 4: for connection with the boiler to conduct steam from 'such boiler to the chamber 5 upon one side of the partition 6, 7 being an outlet from the chamber 8 upon opposite side of said partition to the engine or engines through the union sleeve 9 adapted for suitable connection with such engine.

10 is a check valve adapted to a seat 11 on an end of a bushing 12 screw-threaded, as at 13, into an opening in the partition 6 and provided in its side walls with a plurality of ports or openings 14:.

' The check valve 10 .is provided with a depending portion 15 adapted to slide within the bushing 12, as seen in Fig. 1, being provided with a removable bottom portion 16 threaded or otherwise secured within the lower end of the member 15, and having an opening through which passes the valve stem 17. The depending member 15 is provided with ports or openings 18 near its upper end and with another set of openings or ports 19 near its lower end, as seen clearly in Figs. 1 and 2, and further adjacent the ports 19 with a plurality of smaller ports 20, as seen in Figs. 1, 2 and 3.

The lower portion 21 of the body is made separate from the upper portion 1 and de tachably secured thereto by any suitable means, as the bolts or the like This lower portion is provided with a valve seat 523, see Fig. 1, upon which is adapted to be seated the check valve 24.- depending from and carried by the piston 25, which latter reciprocates bodily within the chamber 26 formed in the lower portion 21.. The check "valve 24 has a depending tubular portion 27 adapted to reciprocate within the cylindrical chamber 28 at the lower end of the portion 21, the lower end of which may be closed in any suitable manner, as by the head 29. 30 is an opening from the atmosphere into the chamber 28 through the wall thereof, as seen in Fig. 1, and the interior of this chamber is provided with an annular counter-bore 31 with which this opening 30 connnunicates. The tubular member 27 depending from the check valve 24 is provided near its upper end with a plurality of small openings 32, as seen in Fig. 1.

Thepiston 25 is provided with a bleed opening 33, as seen in Fig. 1. This piston is also provided with the boss 34 bored longitudinally, as at 85, to serve as a guide for the stem 17 carrying the valve 37 which is fitted to a seat 38 at the upper end of the body portion 39 of the valve 10. The valve stem 17 near its upper end is provided with longitudinal peripheral grooves or the like 40, as seen in Fig. 1, to provide a passage for the exhaust steam from the space between the two pistons, soon to be described, into the chamber 41 formed within the depending portion 15 of the check 10.

The upper part of the body portion 1 is formed with a chamber 42 closed by a removable cap 43 held thereon in any suitable manner and within this chamber 42 is dis posed a double piston 44 comprising the separated piston heads 45 and 46, the former with an opening 47 therethrough and the latter with an opening 48 therethrough, as seen clearly in Fig. 1. These heads are spaced with a space or chamber 49 therebetween, the central web being provided with openings 50, as seen in Fig. 1, com.- municating with the bore above the valve seat 38.

51 is a tubular cap having threaded engagement with the upper end of the double piston and within this hollow cap is a spring 52 having bearing at one end against the inner face of the top of said cap and at its other end against the top of the valve 37.

53 is a spring within the chamber 42, being connected in any suitable manner at one end, as at 54, with the cap 43 and at the other end, as at 55, with the outermost piston head.

56 is a pin which I employ as additional means for fixedly retaining the cap 52 in position on the outermost piston head and preventing relative movement of these parts.

By reason of my present construction as above described and owing to the presence of the double piston, I am enabled to employ softer metals than it has been possible to use in prior constructions of this nature with a single piston on account of the avoidance of the rapid movements heretofore necessary.

With the parts constructed and arranged substantially as above described, the operation, briefly stated, is as follows. The member 4 being connected up with the boiler or source of steam and the member 9, by T- connection or otherwise, with the engines, and steam being admitted through the inlet 2 and the parts being in the position in which they are shown in Fig. 1, the steam enters the chamber 5 and passes through the opening 48in the lower piston head 46 filling the space 49 between the two piston heads and thence through the opening 47 in the upper piston head into the chamber 42, thus equalizing the pressure on both sides and holding the check 10 to its seat, at the same time passing through the ports 50 from the space 49 and acting upon the upper face of the pilot valve 37 holds the latter to its seat. The throttle of the engine being opened, the pressure in the steam pipe from the engine backing up through the passage 7 acting upon the piston 25 forces the valve 24 to its seat and this prevents any leakage and avoids the necessity of the employment of packing rings which have been found to be inadequate for this purpose. The other parts remain in the position in which they are shown. The opening 33 in the piston 25 provides for the equalization of the pressure upon opposite sides of said piston to relieve the piston of the unnecessary pressure upon its upper face. The throttle being closed with the engine moving at a high rate of speed, for the purpose of drifting, the displacement caused by the reciprocation of the pistons of the engine removes the pressure from the chamber 26 upon the upper side of the piston 25 and this displacement created in the space 26 raises the piston 25 and with it the stem 17 which unseats the valve 37 against the pressure of the spring 52, allowing the pressure in the space 49 between the two pistons to exhaust downward through the grooves 40 of the stem 17 into the chamber 41 and out through the openings 20, through the openings 14 in the depending portion 12 of the bushing and into the space 26. The pressure in the chamber 42 is thus relieved through the opening 47 in the piston head 45, through the ports 50 and the grooves 40 in the stem and thence through the ports 20 and 14 to the chamber 26. When the pressure in the chamber 5 becomes greater than the pressure upon the outer face of the check 10, the check 10 is lifted and with it the pistons 45 and 46, when the pressure in the chamber 5 escapes through the openings 18 into the chamber 41 and thence through the openings or ports 19 and ports 14 into the chamber 26. The bottom 16 of the depending portion 15 of the check 10 receives the impact of the steam when the check 10 is raised and thus serves to balance the same, thus allowing the pistons to control the movement of the check 10 gradually, avoiding the heretofore rapidity of movement of said check to and from its seat.

When the piston 25 is raised, as above described, the atmospheric air entering through the port 30 passing around the annular counterbore 81 enters the interior of the depending skirt or portion 27 and passing through the ports 32 enters the space in the chamber 26 below the piston 25.. This air seeping through the passage 33 in the piston 25 and mixing with the saturated steam in the space 26, causes the steam to become more latent which will satisfy the vacuum created in the cylinders of the engine more readily than otherwise would be the case with steam at high temperature and less latent temperature. As soon as the throttle is again opened, the parts all return automatically to their normal position, that shown in Fig. 1. It will be noted that by the construction above described, I employ only positive means to insure against leakage, and when the throttle is open the valve is inoperative, the parts all remaining in the position in which they are seen in Fig. 1, to be actuated only when the throttle is closed and the engine under speed and driftmg.

Modifications in details may be resorted to without departing from the spirit of the invention or sacrificing any of its advan tages.

The spring 53 while serving to seat the valve 10 or to assist in its seating, serves an important function in that it overcomes all tendency of the double piston and said valve 10 to rotate within the cylinder.

It is to be noted that the ports 32 in the depending skirt 27 of the check valve 24; are disposed at a point slightly below the seating point of the said valve so that when the valve is in its raised position the said ports are in communication with the space beneath the piston 25, when the valve commences to seat this communication is shut off in advance of its final seating, thus producing a cushioning effect by the confinement of the air within the space beneath said piston acting on the larger area of the piston, thus insuring a gradual and easy seating of the valve.

What is claimed as new is 1. In a drifting valve for locomotives, a double piston, a check valve carried thereby, and a piston-controlled check valve carried by said double piston with means for permitting the exhaust from the space between said pistons.

2. In a drifting valve for locomotives, a

double piston, a check valvemovable therewith and having a depending portion with ports, a valve seated on said piston and having a stem with escape passages, and a piston for actuating said valves.

3. In a drifting valve for locomotives, a check valve, separated pistons movable therewith, a valve movable in the space be tween said pistons, and means for permitting the exhaust from the space between said pistons.

4. In a drifting valve for locomotives, a check valve, separated pistons movable therewith, a valve movable in the space between said pistons, mcans for permitting the exhaust from the space between said pistons, and a check valve movable with said pistons.

5. In a drifting valve for locomotives, a check, valve, separated pistons movable therewith, a valve movable in the space between said pistons, means for permitting the exhaust from the space between said pistons, a check valve movable with said pistons, and a check valve for moving the stem of the first-named valve in one direction.

6. In a drifting valve for locomotives, a check valve, separated pistons movable therewith, a valve movable in the space between said pistons, means for permitting the exhaust from the space between said pistons, a check valve movable with said pistons, a check valve for moving the stem of the firstnamed valve in one direction, and a spring bearing against said valve to move it in the opposite direction.

7 In a drifting valve for locomotives, a check valve having a depending portion with ports, separate pistons movable therewith, a valve movable in the space between said pistons, a bushing having a seat for said valve, and also provided with ports, a valve movable with relation to said check valve, and a piston for moving the lastnamed valve in one direction.

8. In a drifting valve for locomotives, a check valve having a depending portion with ports, a bushing having a seat for said valve and also provided with ports, a valve movable with relation to said check valve, and a piston for moving the last-named valve in one direction, said depending portion having a bottom serving as a means to balance the check valve.

9. In a drifting valve for locomotives, a piston,a valve movable thereby in one direction, a check valve and a double piston movable therewith, said double piston having ports communicating with the space between the pistons from opposite sides thereof.

10. In a drifting valve for locomotives, a piston, a valve movable thereby in one direction, a check valve and a double piston movable therewith, said double piston having ports communicating with the space be 'tween the pistons from opposite sides thereof, and means for balancing the check valve.

11. In a drifting valve for locomotives, a check valve, a double piston carried thereby, a valve having a stern movable through the body of the check valve, a piston for moving said stem in one direction and means for ex hausting from the space between the heads of the double piston by way of said valve stem.

12. In a drifting valve for locomotives, a check valve, a double piston carried thereby, a valve having a stem movable through the body of the check valve, a piston for moving said stem in one direction and means for exhausting from the space between the heads of the double piston by way of said valve stem, said check valve having a ported depending portion,

13. In a drifting valve for locomotives, a check valve, a double piston carried thereby, a valve having a stem movable through the body of the check valve, a piston for moving said stem in one direction, means for exhausting from the space between the heads of the double piston by way of said valve stem, said check valve having a ported depending portion, and a bushing having a seat for the check valve and a depending portion with lateral ports.

14. In a drifting valve for locomotives, a piston having a tubular depending portion with ports, a casing within which said depending portion is movable provided with an annular counterbore and a port leading to the atmosphere, a check valve carried by said depending portion, and a port extended through said piston.

15. In a drifting valve for locomotives, a piston having a tubular depending portion with ports, a casing within which said depending portion is movable provided with an annular counterbore and a port leading to the atmosphere, a check valve carried by said depending portion, a port extended through said piston, and a valve having a stem guided in and actuated by said piston.

16. In a drifting valve for locomotives, a piston having a tubular depending portion with ports. a casing within which said depending portion is movable provided with an annular counterbore and a port leading to the atmosphere, a check valve carried by said depending portion, a port extended through said piston, a valve having a stem guided in and actuated by said piston, and a double piston provided with a check valve.

17 In a drifting valve for locomotives, a piston having a tubular depending por tion with ports, a casing within which said depending portion is movable provided with an annular counterbore and a port leading to the atmosphere, a check valve carried by said depending portion, a port extended through said piston, a valve having a stem guided in and actuated by said piston, a double piston provided with a check valve, and a seat for the first-named valve.

18. In a drifting valve for locomotives, a piston having a tubular depending portion with ports, a casing within which said depending portion is movable provided with an annular counterbore and a port leading tothe atmosphere, a check valve carried by said depending portion, a port extended through said piston, a valve having a stem guided in and actuated by said piston, a double piston provided with a check valve, and a seat for the first-named valve, said stem having longitudinal grooves.

19. In a drifting valve for locomotives, a piston having a tubular depending portion with ports, a casing within which said depending portion is movable provided with an annular counterbore and a port leading to the atmosphere, a' check valve carried by said depending portion, a port extended through said piston, a valve having a stem guided in and actuated 'by said piston, a double piston provided with a check valve, a seat for the first-named valve, said stem having longitudinal grooves, the check valve carried by the double piston having a depending portion with ports.

20. In a drifting valve for locomotives, a piston having a tubular depending portion with ports, a casing within which said depending portion is movable provided with an annular counterbore and a port leading to the atmosphere, a check valve carried by said depending portion, a port extended through said piston, a valve having a stem guided in and actuated by said piston, a double piston provided with a check valve, a seat for the first-named valve, said stem having longitudinal grooves, the check valve carried by the double piston having a depending portion with ports, and a bushing having a seat for said check valve and a depending portion with lateral ports.

21. In a drifting valve, a double piston having a valve seat and a tubular cap, a valve adapted to said seat and having a stem, a piston for moving said valve in one direction, and a spring within said cap exerting its influence upon said valve in the opposite direction.

22. In a drifting valve for locomotives, a reciprocatory piston, and a spring movable therewith and connected thereto and to a relatively fixed part to prevent rotary movement of said piston.

23. In a drifting valve for locomotives, a reciprocatory piston, a casing in which it is adapted to reciprocate, a closure for one end of said casing, and a spring movable with said piston and connected thereto and to said closure to prevent rotary movement and a tubular depending portion carried by of the piston. said check valve and having ports below the 24. In a drifting valve for locomotives, seating point of the valve to cushion the a casing, a reciprooatory piston therein, a latter. 5 check valve carried by the piston, and means In testimony whereof I alfix my signature 5 movable with the piston and assisting in in presence of two witnesses.

seating said valve and preventing rotary VINCEN P. MGVOY. movement of the piston. Witnesses:

25. In a drifting valve for locomotives, JOHN SGRIVENER, 10 a piston, a check valve movable therewith E. H. BOND.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents.

/ Washington, D. G. 

